Construction of roads having alpha foundation course of sand



March 12, 1929. 5, sQs R 1,705,068

CONSTRUCTION OF ROAD HAVING A FOUNDATION COURSE OF SAND Filed Aug. 28,1926 Samuelfi 5a alt/er,

TNES 434W Y, M

Patented Mar. 12,1929.

UNITED STATES PATENT" or FICE.

. saimnr. s. SADTLEB, or srmnormnn 'rownsnrr, mou'reounmr COUNTY,ramminvanm, ASSIGNORTO mmsrrr. FOUNDATION country, A CORPORATION or DELLCONSTRUCTION OF ROADS HAVING A FOUNDATION COURSE OF BAND.

Application ma August as, 1926. Serial no. 131137.

My invention relates to the construction of roads, particularly. insandy soils and it is theaim and purpose of my invention to utilize suchsand as the foundation course of f the roadway. 1

A further object of my invention is to simplify and reduce the cost ofbuilding satisfactory roads through a sandy soil by rendering the roadfoundation composed of such sand sufficiently rigid to prevent lateralmovement of the sand after the road is constructed.

A further. object is to provide a road construction wherein sand is usedas the main and essential constituent of the foundation course andwherein such sand is protected from theaction of Water thereon and fromliability of being shifted laterally under the load of trafiic thereon.

A further object of my invention is to provide a road constructionwherein the load of moving 'trafiic on the surface thereof will betransmitted to a foundation course of normally shifting consistency, butover a relativelylarge area of said foundation course, by two courses ofdifferent flexible fabrics between the foundation course-and the top orsurface course and operative to prevent any lateral or transversemovement of the material comprising the foundation course.

Other objects of my invention will appear in the. specification andclaims below.

In the'drawings forming a part of this 5 specification and in which thesame reference characters are used throughout the various views todesignate the same parts.

1 is a somewhat diagrammatic view in transverse cross-section, of. aroad em- 0 bodying my invention with the various courses or layersemployed in the construc tion spaced one above the other and Fig. 2

is a similar cross-sectional view of the completed roadway.

half of a complete cross-section of the road is indicated in the drawins it being understood that both sides of t e road are alike.

Nor do the drawings strictly indicate the relative sizes of the various.courses of the road. The thickngs: of certain coupses lis eatl exagerate o the purpose 0 ma i nfg th e con structionffiar in the drawings.

In these drawings a little more than one- This will be referred to againbelow with more particularity.

In making a road through a sandy soil 1,

Ifirst bring the surface of the soil to the top 2 of the foundationlevel by dragging or excavating to provide a foundation 2 of sand havingthe necessary grade and crown.

The foundation 2 of sand having been' crowned and graded I thenpreferably form on opposite sides of the foundation 2 suitable trenches3 for the reception of the curbing 4 which. is preferably of concretecast in ing 4 provides a retaining wall which prevents lateral movementof the said founda tion 2. I I

Inbringing the top 2' of the. foundationlevel to proper grade and crown,I may have inserted into the sand suitable stakes 6 (preferablycreosoted),' the tops of which are positioned so as to indicate thelevel or plane to which the top of the foundation should be brought.If,'however, such stakes were not used in the making of the foundation,then I may insert suchstakes 6 (preferably creosoted) into the crownedfoundation driving them down until the tops thereof are flush with thetop surface 2, of the foundation course 2. In ei'thercase'I'preferablyposition a row or series of stakes 6 relatively close to the curbing 4so that a subsequent course of the road may be secured thereto along thesides of the -road adjacent the curbing as will be referred to againbelow.

In order to compact the sand of the foundation course 2, I preferablywet it with water to make the course damp to a depth of from 6 to 10inches. Over the surface vor top 2 of this damp compacted foundationcourse 2, I then lay a protective course 7 composed of :strips or piecesor sheets 7. of a coarse textile fabric, which may be the jute baggingin which lime and similar materials are usually contained. The adjacentedges of these sheets 7' of textile fabric are overlapped to shed wateras clearly indicated in the drawings. This protective fabric course 7when treated as described below, is to prevent water from above fromentering the traffic over a large area of-the foundation 7 ging a smallamount or layer or course of,

sand foundation after the road is completed and to assist indistributing the load of course. After the textile fabric has been thusplaced over the surface 2 of the founelation, I apply to the uppersurface thereof a course or layer or sprinkling or painting 8 ofasphaltic material, such as asphaltic road oil, which may be heated torender it quite liquid and capable of being absorbed by the fabric. Ipreferably provide more of this thin liquid than'can be absorbed by thefabric so that this asphaltic oil will pene-.

trate and pass through the coarse fabric and become mixed with the sandbelow the fabric. After the oil has been thus applied, I may sprinkleover the upper surface of the bagsand 9 to absorb the excess oil abovethe fabric course v7. When this has been done and the roadway iscompleted there will be above and below the fibrous fabric 8 acomparatively thin or light course 89, composed of sand intermixed withasphaltic oil." U

On top of this course 89, on the fabric 8, I then lay a course 10 offabricated metal material, such as galvanized chicken wire, ofpreferably: about oneinch mesh and I secure it to the posts or stakes 6.by any suitable fastening means 11, such as nails, tacks or staples. Inso securing the wire mesh fabric 10 to the stakes I stretch it so thatit will lie smoothly down on the upper surface of the coarse fabric 8 orthe thin course 89 of asphalt and sand thereon. This chicken wire isobtainable in strips of suit able width and in laying it upon thefoundation, as above described, I preferably bind the edges of adjacentstrips firmly together with wire.

The len th of each strip of wire fabric is prefera ly somewhat longer;than the distance between opposite curbs so that the ends thereof may bebent and lapped up against the curbin 4. In this way the'wire fabric 10and the fibrous fabric course 7 are securely attached or anchored tothe. posts 6' in the foundation 2 and bed of the roadway.

Although the wire mesh fabric 10 is preferably a galvanized wire fabric,I prefer to make it certain that it is thoroughly protect.- ed fromcorrosion. I, therefore, over the wire fabric, next preferably lay orsprea' or sprinkle a coating or course .12 of asphalt-i c material, suchas asphaltic oil or liquid'ase phalt so as to thoroughly coat thestrands of the wire mesh fabric with asphalt.' In Fig.

2 of the drawing, this course 12 of asphalt-i0 material appears asresting on or above the top of the wire mesh fabricIO but, of course, inpractice, the asphaltic material will settle down into the wire meshfabric 10, and la ers 89 on each side thereof. In the wire fa ric themesh'i's preferably of about lone-inch. Moreover, the size-of the nailsand the size After the surface course 18 has been placed, it ispreferably given a thin dusting or coating 14, of cement, sand or othermaterial'and rolled with a heavy roller, thus compacting the wholeroadway and bringing it to the level of the inner edge-of the gutters 5when the curbing 4 is' provided with-gutters.

A road constructed in the manner above set forth and having a surfacecourse of amiesite or similar black surfacing material operates undertraffic to transmit the load of traffic from the surface course 13 bythe two fabric courses 10 and7 t0 the sand foundation 2 but in thistransmitting the load, they distribute it over a relatively wide area ofthe sand foundation course so that the sand or foundation course is notpressed or moved transversely or laterally but offers a firm rigidsupport for the traffic or load on the road.

When desirable may treatthe sand foundation 2 chemically} before placingthereon the bag ing cdurse 7 Thus instead of compacting t e sand bysprinkhng water thereon, I may sprinkle it'with a liquidmixture' ofsilicate of soda, sulphuric acid'and water to compact it and to' makethe sand more rigid and water-resisting. I'may form The amount of sulhuric acid to the sodium silicate solution being substantially as 1 to4.

When this solution dries it becomes insoluble and the sand foundationwill be provided with a crust downwardly into the foundation course'fromthe surface thereof.

In the roadabove constructedl have thus provided two courses ofdifferent materials for distributing the load of the traflic on the theliquid by mixing substantially 10 volumes of a commercial grade ofsilicate of soda, diluted with 90 volumes of water, with 'a 10% aqueoussolution of sulphuric acid.

road over a large area with the sand foundation. The course 7 of baggingpreserves the surface 2' on the sand oundation stationary. That is tosay, the traffic does not cut into it. The textile fabric-holds thesurface'stationa although of itself the bagging-is very exible and thewire mesh fab ric 10 distributes the load over -it.' The course 10 offabrieatedwire is more rigid and has great tensile strength. 1 It issecure- 1y anchored to the posts 6 as above described but is preventedfrom sinking into the sand under the load on the surface by the fabriccourse 7. v

The wire mesh fabric therefore substantially rests on a sand foundationcourse which virtually has a tough inextensible upper surface, formed bythe textile fabric course, on which the wire mesh fabric lies,

and the wire mesh fabric spreads and distributes the load of trafficover a relatively large area of sand foundation made firm by the textilefabric course.

flush with thcitop of said foundation course,

sheets of coarse woven textile fabric having their adjacent edgesoverlapped to shed water laid on the top of said foundation course,strips of reticular metal fabric laid on said textile fabric, fasteningmeans securing said textile fabric and said metal fabric to the tops ofsaid osts, the top surface of said textile and t e metal fabric beingcoated with a surface of liquid asphaltic material,

and a surface course of stone aggregate bound together with asphalticmaterial supported on said reticular metal fabric.

2. A roadway comprising a foundation course composed of sandy soil, acourse of jute bagging coated with liquid asphaltic material lying onthe top of said sand foundation, strips of open mesh metal fabriclyingon said fibrous material and coated with said liquid asphaltic material,and a surface course of stone aggregate bound together with asphalticmaterial supported on said metal fabric, the stone aggregate in saidsurface course and adjacent said metal fabric being of a size lar erthan the size of the mesh in said metalfa ric.

3. A roadway comprising a foundation course composed of sandy soil, limeand water and having a series of stakes therein extending alon edgesthereo a fibrous course comprising sheets of, coarse woven jute fabricon the surface of said foundation course with their adjacent edgesoverlapping to shed. water and impregnated with liquid asphalticmaterial, strips of open mesh wire fabric lying on said jute fabriccourse and coated with liquid asphaltic material, the adjacent edges ofsaid wire mesh fabric being secured together and means to secure saidwire fabric and said jute fabric course to the top ends the roadway nearthe sideof said -stakes, and a surface course on said metal fabriccomprisin stone aggregate bound together with asp altic material.

4. A roadway comprising a foundation course of sand wctted and compactedwith a mixture of silicate of soda, sulphuric acid and water, a courseof coarse woven' textile fabric impregnated with a liquid asphalt lyingon said sand foundation, an.o en mesh metal fabric lying on said aspha tcoated textile fabric course, and a surface course of stone aggregate,the stones of which are coatedand bound together with an asphalticmaterial, the stone aggregate in said course adjacent saidmetal fabricbeing of a size larger than the size of the mesh in said metal fabric. I

In witness whereof, I have hereunto set my hand this 26th day of August,1926.

SAMUEL s. SADTLER.

